Piston ring compressor



f March 23, 1965 w. .1. HUIGENS ETAL 3,174,215

PISTON RING COMPRESSOR Filed March 5, 1962 ATTUR/VEYS.

In L

United States Patent Ofice 3,174,215 Patented Mar. 23, 1965 3,174,215PISTON RING COMPRESSOR Wilfred J. Huigens and Glenn Larkin Keeran,Clarinda,

Iowa, and Gerald N. MeAnlifie, Lincoln, Nehru, assignors to LisleCorporation, Clarinda, Iowa, a corporation of Iowa Filed Mar. 5, 1962,Ser. No. 177,673 2 Claims. (Cl. 29-222) This invention relates to apiston ring compressor to facilitate the compression of piston rings inthe grooves of a piston preparatory to inserting the piston in acylinder.

One object of the invention is to provide a piston ring compressor ofthe general type having a compression band surrounded by a tension band,and winding means for the tension hand, our compressor being furtherprovided with a means to prevent reverse rotation of the winding meansin infinitely small steps as distinguished from ratchet and pawl devicesfor this purpose.

Another object is to provide a holding coil spring tightly wound arounda winding drum and having one end anchored so that rotation of thewinding drum in the Winding direction tends to enlarge the diameter ofthe coil spring. Accordingly the coil spring automatically reduces indiameter and grips the winding spool to prevent reverse rotation thereofas soon as the handle for operating the winding drum is released.

Still another object is to provide the holding coil spring with manuallyoperable means for increasing its diameter so as to release the windingdrum and permit it to rotate reversely when desired.

A further object is to provide another spring wound around the windingdrum and frictionally but lightly engaging it so as to act as snubbingmeans to prevent free reverse rotation of the winding drum which, in theabsence or" the snubbing spring, would rapidly rotate because of thetendency of the compression band to expand in diameter when permitted todo so.

Further objects and advantages of this invention will become apparent asthe following description proceeds and the features of novelty whichcharacterize this invention will be pointed out with particularity inthe claims annexed to and forming part of this specification.

A preferred embodiment of the invention is shown in the accompanyingdrawings, in which:

FIG. 1 is a side elevation of a piston ring compressor embodying ourinvention;

FIG. 2 is a bottom plan view thereof showing it applied to a piston;

FIGS. 3, 4 and are sectional views on the lines 33, 44 and 55respectively of FIG. 1; and

FIG. 6 is an exploded perspective view of a winding drum, a holdingspring, and a snubbing spring of our device.

On the accompanying drawing we have used the reference numerals 10 toindicate a compression band of spring steel or the like and 12 a tensionband surrounding the compression band. One or more of the bands 12 maybe provided, two being shown on the drawing. The bands 12 are of thinflexible steel capable of being wound on a drum 28. The drum 28 istubular as shown in FIG. 3 so that rivets 15 may be inserted therein,then countersink-riveted as indicated at 17 to one end of each band 12.The other end of each band 12 is riveted, each by a rivet 24, to abearing bracket 22 stamped from sheet metal and provided with fourtubular bearings 26 to rotatably support the winding drum 28.

One end of the compression band 10 is also riveted at 24 to the bracket22 and the band extends about one and one-half times around a piston 16as shown in FIG. 2, the connecting rod of which is shown at 18. Thepiston 16 has one or more rings 20 therein to be compressed by the band10, and an overlapping arrangement of this band permits it to beadjusted to pistons of greater and less diameter than shown in FIG. 2 sothat the device is readily adjustable to various sizes of pistons in anobvious manner.

A handle 30 is provided for rotating the winding drum 28counterclockwise in FIG. 3 as indicated by the arrow a, thus Winding thetension bands 12 thereon for decreasing the diameter of the compressionband 10 and thereby compressing the rings 20 into the grooves of thepiston 16 to facilitate entry of the piston and rings into a cylinder.

To prevent reverse rotation of the drum 28 without the necessity ofhaving to hold the handle 30, a holding spring 32 is provided consistingof several coils wound tightly around the drum 28 for frictionallyengaging the same and holding it against reverse rotation. The crosssection of the wire used for this purpose is preferably square so as toprovide considerable surface area between the inside diameter of theholding spring and the outside diameter of the winding drum, and thespring is wound so that its inside diameter is several thousandths of aninch smaller than the drum. One end arm of the coil spring 32 indicatedat 34 is anchored to the bracket 22 by insertion in a head 36 formed onthe outer traverse thereof, and a rivet 25 is used to prevent spreadingof the rib with respect to the inner traverse of the bracket 22. Theterminal end of the arm 34 is bent at right angles as indicated at 38 toprovide better anchorage. That end of the coil spring 32 is anchoredwhich causes the drum 28, in rotating in its winding direction a in FIG.5, to tend to unwind the spring and thereby increase its diameter sothat the winding drum 28 may be readily rotated in the windingdirection. However, when rotation stops by release of the handle 30, thedrum will rotate reversely only a very small fraction of a degree underthe winding up tendency of the holding spring 32, and the spring willthereupon grip the drum and hold it against reverse rotation. Adjustmentcan thus be secured in infinitely small steps as distinguished from aratchet-type device in which the steps are of necessity several degreesin extent.

The other end arm 40 of the holding spring has a handle 42 thereon whichmay be engaged and pushed in the direction of arrow b in FIG. 5 forexpanding the diameter of the coil 32 and thereby releasing the windingdrum to permit its reverse rotation when it is desirable to remove thepiston ring compressor from the piston. Thus the holding spring 32 isreadily operable in a release direction when desired.

The compression band 10 is initially a straight strip of spring steeland accordingly has considerable tendency to expand in diameter when thewinding drum 28 is released. It would therefore be necessary to hold thehandle 30 against rampant rotation in the reverse direction and possibledamage to the piston ring compressor, but this is an awkward operation.

Accordingly, we have provided a snubber spring 44 shown in FIG. 4 whichis similar to the spring 32 but has less than one coil, and is woundonly lightly on the drum 28 as for instance being only about .001"smaller in diameter than the winding drum. This spring has its end 46 ina second bead 48 of the bracket 22. The direction of winding is the sameas the spring 32 and accordingly the diameter tends to expand on windingrotation in the direction of arrow a and to decrease when the directionis reversed. Since this spring is only lightly engaged frictionally withthe drum 28, however, it holds the drum against free rotation butpermits manual reverse rotation by operation of the handle 30 so as togently unwind the coils of the band 12 from about the Winding drum 28instead of permitting violent unwinding as would be the case if thesnubber spring 44 were omitted.

3 While less than one coil forthe spring 32 is illustrated anddescribed, it may be a multiple coil spring and made of lighter springwire than the spring 32 yet accomplish the desired result of ,onlyafraction of thefrictional drag on the drum 28.as compared withthespring 32..

While there has been shown and described a particular embodiment of thisinvention, it will be obvious to those skilled in the ,art that variouschanges, and, modifications may be made therein without departing fromtheinvention and,,therefore,'it, is intended in-the appended claims tocover all such changes and modifications as fall within the true spiritand scope of the invention. v

a What we claim as new, and desire to secure by Letters Patent of the,United States, is:

,1.'In ,a pistonring compressor, a compression band .,-adapted forassuming. the shape of the piston which carsaid tension band woundthereon,,and means to prevent reverse rotationof said drum comprising aholding coil spring wound therearoundand frictionally engaging the outersurface thereof, one end, of said holding coil spring being fixedrelative to said tension band and the other end thereof being free, thedirection of winding of .said spring being such that there is a tendencyto unwind it assaid drum is rotated for decreasing the diameter of saidten- 'ries' the rings to be compressed, said compression band being inthe form oi a split ring having overlapping ends to permit relativemovement between said ends, a tension band of flexible materialencircling said compression band for holding it in positiona'nddte'rr'nining the diameter of said compression band, means connectedto said tension band for' varying the effective diameter thereof, saidmeans comprising a winding drum rotatably carried by one end of saidcompression band and having one end of said tension band wound thereon,and'mea'ns'to pre. vent reverse rotation of said drum comprisinga'rele'asable holding coil spring Wound therearound 'andfrictionallyengaging 'the outer surface thereof and a'sriubbing coil spring havingonefend connected to said"compre'ssion band, its other end free and itscoil'lightly'and frictionally engaging around the periphery of saidwinding drum for snubbing the same against rapid reverse rotation whensaid holding coil spring is released.

References Cited'in the file of this patent UNITED STATES PATENTS

1. IN A PISTON RING COMPRESSOR, A COMPRESSION BAND ADAPTED FOR ASSUMINGTHE SHAPE OF THE PISTON WHICH CARRIES THE RINGS TO BE COMPRESSED, SAIDCOMPRESSION BAND BEING IN THE FORM OF A SPLIT RING HAVING OVERLAPPINGENDS TO PERMIT RELATIVE MOVEMENT BETWEEN SAID ENDS, A TENSION BAND OFFLEXIBLE MATERIAL ENCIRCLING SAID COMPRESSION BAND FOR HOLDING IT INPOSITION AND DETERMINING THE DIAETER OF SAID COMPRESSION BAND, MEANSCONNECTED TO SAID TENSION BAND FOR VARYING THE EFFECTIVE DIAMETERTHEREOF, SAID MEANS COMPRISING A WINDING DRUM ROTATABLY CARRIED BY ONEEND OF SAID TENSION BAND AND HAVING ONE END OF SAID TENSION BAND WOUNDTHEREON, AND MEANS TO PREVENT REVERSE ROTATION OF SAID DRUM COMPRISING AHOLDING COIL SPRING WOUND THEREAROUND AND FRICTIONALLY ENGAGING THEOUTER SURFACE THEREOF, ONE END OF SAID HOLDING COIL SPRING BEING FIXEDRELATIVE TO SAID TENSION BAND AND THE OTHER END THEREOF BEING FREE, THEDIRECTION OF WINDING OF SAID SPRING BEING SUCH THAT THERE IS A TENDENCYTO UNWIND IT AS SAID DRUM IS ROTATED FOR DECREASING THE DIAMETER OF SAIDTENSION BAND, AND SAID FREE END TERMINATING IN A LEVER PORTIONPROJECTING BEYOND THE DIAMETER OF THE COIL WHICH IS MANUALLY ENGAGABLEFOR INCREASING THE DIAMETER OF SAID HOLDING COIL SPRING WHEN SAID LEVERPORTION IS MOVED IN THE DIRECTION OF WINDING TO THEREBY PERMIT REVERSEROTATION OF SAID DRUM.